挖坑机钻头的有限元分析与试验

为进一步合理设计钻头结构，采取理论与试验相结合的研究方法，对挖坑机钻头进行了挖坑试验和有限元法的静态与动态分析。通过挖坑试验得到2种典型工况下钻头的最大扭矩和铅垂阻力，将试验得到的最大阻力作为外载施加到钻头的三维实体模型上，利用有限元方法对挖坑机钻头进行静力学和模态分析。结果表明:钻头的最大等效应力为111.0 MPa，位于主刀架和主刀的连接螺栓孔内壁上；最大变形位移为0.68 mm，位于主切削刃最外角点。前6阶固有频率振型中，除了体现钻头整体扭转振动的第3阶模态有利于减小阻力及应力集中外，其余5阶振型均不利于钻头的平稳工作，应尽量避免。 

Finite element analysis and experiments on the drill of earth auger

In order to provide basic theory for the novel structural design of earth auger, the hole digging experiments and then the static and modal finite element analysis were carried out, combining the theory and experiment. The vertical resistance and torque on the drill were obtained from the digging experiments, which were applied on the 3D drill physical model. And the finite element method was used in this simulative study. The static simulative results showed that the largest Mises stress value was 111.0 MPa, locating at the inwall of the bolt hole connecting the main cutting blade and its shelf, and the largest deforming displacement value was 0.68 mm, locating at the out corner of main cutting blade. The first six natural frequencies and modes were provided by model analysis, and five modes of the six will increase the vibration of the drill, except for the third one, which is good for the decrease of resistance and stress concentration.